7. Use the "Browse" button to locate a picture to upload from your computer.

Note: Images currently can't be more than 500 pixels wide or tall, or over 256kb in file size to be allowed in the profile gallery.

If you are unable to upload photos they are likely too large in pixel dimensions or file size. Use an application like photoshop, iPhoto etc to reduce the file size to a more "web friendly" format. Read the error message which appears if you have a problem uploading. That message will tell you what was wrong with the file you attempted to upload.